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P. MEDART.

BELT SHIFT ER No. 402,758. Patented May 7, 1889.,

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P. MED ART. BELT SHIPTER (No Model.)

, No. 402,758. l atented May 7, 1889.

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No. 402,763. l atented May 7, 1889. Y

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UNITED STATES PATENT O FICE.

PHILIP MEDART, OF ST. LOUIS, MISSOURI, ASSIGNOR OF ONE-HALF TO I IVILLIAM MEDART, OF SAME PLACE.

BELT-SHIFTER.

SPECIFICATION formingpart of Letters Patent l\To. 402,758, dated May 7,1889,

I Application filed February 19,1889, Serial No. 800,490- (No model.)

To all whom it may concern:

Be it known that I, PHILIP MEDART, a citizen of the United States,and a resident of the city of St. Louis, in the State of Missouri, have invented certain new and useful Improvements in Belt-Shifters, of which the following is a specification.

My invention relates to belt-shifters of that class in which the belt is slackened on the pulley in contradistinction to shifting it latg orally from a fast to a loose pulley.

The objects of my invention are to secure the'proper tension of the belt while running, and to protect it from wear when shifted or slack upon the pulleys. These e lds l attain by causing lifting barsoi-l-oilers simultaneously to traverse concentrically or parallel with the face of the pulley in opposite directions, to interpose the bars or rollers between the pulley and its belt, and to lift and hold the belt clear of the pulley. I also employabelttightener in connection with the lifting bars or rollers.

The subjectmatter claimed is hereinafter specifically designated.

The accompanying drawings represent so much of an apparatus embodying my improvements as is necessary to illustrate the subj cot-matter claimed.

Figure 1 is a vertical longitudinal section therethrough, and Fig. 2 a side elevation thereof; Fig. 3, a sectional plan view in the horizontal plane of the driving-shaft. Fig. 4 is a perspective detail view showing the mode of connecting one set of the lifting-roller arms with the shaft. Fig. 5 shows a similar view of another set of lifting-roller arms and Fig. 6 shows in elevation a modification of the apparatus with the tightening-pulley below the belt and a suspendedactuating-lever and pulleys. Fig. 7 represents a perspective detail view of the tightening pulley and its attaching arms; Fig. 8, a perspective view of the tighteningbelt suspension-yoke of Fig. 6; Fig. 9, a section showing the mode of connecting the shifter-arms and shaft; Fig. 10, side'and edge views of one of the arms, showing the way in which they are made adjustable in. length;

and Fig. 11 shows details of the sleeves and collars used in connection with the shiftingarms.

A driving shaft, A, mounted in suitable bearings, B, carries a driving-pulley, O. A driven shaft, 1), having a driven pulley, D, thereon, also turns in the usual bearings. Collars a are secured on the shaft A, adjacent to and on each side of the hub of-the pulley C, but out of contact therewith. I A sleeve, 1), Fig. 9, also mounted on the shaft A on each side of this pulley, is interposed between a collar, a, and a collar, b, also secured to the shaft A. Radial shifting-armsEare mounted on these sleeves 1) between the collars a and b. The drawings show four such arms separately pivoted on each side of the drivingpulley and connected at their outer ends in pairs'or sets, each set independent of the other, by cross bars or pieces E, on which friction-rollers E are preferably mounted. These rollers, it will be observed, move concentrically parallel with the surface of the pulley, to interpose between the pulley and belt whenactuated by the other parts of the shifting mechanism.

Fig.4 shows the lower ends, 6, of the shifter-arms E as provided with annular bearingsurfaces 6 open or split at e. The width of these openings 6 approximates but slightly the diameter of the shaft A. Consequently the arms may be slid laterally on the shaft,

so as to bring their central openings in line therewith, when the arms may be slid in a transverse direction on the sleeves I). These sleeves and the collars b are then brought together and the collars a b tightened on the shaft, while the sleeve 1) remains loose, thus holding the the arms securely in position on the sleeves, while leaving them free to turn thereon. By this means wear on the bearing of the arms is avoided to a great extent, as the shaft does not come in contact with their bearing-surfaces. g

Fig. 9 shows the arms as made in sections, longitudinally slotted and connected by clamp-screws to admit of their longitudinal adjustment to accommodate pulleys of different diameters. This adjustment may also be effected in other well-known ways.

The collars a b and sleeves b may be made formed with inwardly-projecting lugs or nibs- 6 which engage at times with the. adjacent arms E of the other or loose set to move them positively, as will be hereinafter more fully described. The link-rods F are pivoted at one end to the arms E and at the other to an operating-lever, G.

The l oose arms E and positively-actuated arms E are shown in Fig. 1 as brought close together 011 one side of the pulley, between.

it and the belt and out of contact therewith. This is the relative position of the arms when the driving-pulley and belt are in motion. lVhen it is desired to disconnect the belt from the pulley, the lever G is retracted, as 111 Fig. 2, and the yoke or link-rods F draw the radial shifting-arms E E in opposite directions around the shaft into the position shown in Fig. 2, in which the arms E are shown as interposed between the belt and pulley on that side of the driving-shaft and driving-pulley opposite to the driven shaft,

and the arms E, respectively, extend upward and downward, holding the lifting-rollers E above and beneath the pulley, but out of contact therewith. It will thus be seen that the driving-belt is removed from contact with the' periphery of the pulley l3 evenly and without undue strain on the belt, and very little slack of the belt is required to permit the arms to operate. The pulley, while free to revolve, permits the driving-belt to stop, and as there is no contact of the belt with the pulley friction or wear is avoided.

In connection with this device I employ a belt-tightener, which consists of a pulley, H, carried by arms H, shown as pivoted to the driving-shaftAor to the sleeve 17 on said shaft. The bearing-surfaces h of the arms H are split or open, like the arms above described, so as to be readily inserted on the sleeve. The pulley H follows the belt and keeps it sufficiently taut operatively to connect the driving-pulley with the driven pulley. hen the belt is lifted from the driving-pulley, as in Fig. 2, the tightening -pulley H is readily lifted, as shown in said figure, to accommodate the changed position of the belt.

It will be observed that when the arms E are retracted to lift the belt from the pulley B the lugs or nibs e engage with the loose arms E and cause them to move together with the arms E for a proper distance. The lugs or nibs e engage with the arms E after the arms E have moved part way back, so that when the arms reach the extremity of their backward movement the rollers E are arranged equidistantly, or approximately so, about the pulley. It is of course not necessary that the arms should be thus arranged,

but it is desirable. It is likewise possible to employless than four pairs of arms, as illustrated, it being necessary only to so arrange the arms that by their separation and approximation the driving-belt may be lifted or removed entirely out of contact with the pulley and then allowed to resume its normal position in contact with the pulley when it is desired to again start the machinery.

Fig. 6 shows an arrangement of the several parts similar to that described in connection with the other figures, except that in this figure the bearings are shown as suspended and the ti ghtenin g-pulley is beneath the belt. Said pulley being mounted in arms free to rock 011 the driving-shaft will necessarily require some means of support and some means for moving it coincidently with the movement of the belt-shifter. The arms H. are shown as connected with the upper end of the operatinglever G by means of ropes, cords, or chains 9, which pass over a pulley, I, secured to the ceiling. The arms 11 are shown as connected to the bale or yoke J, in turn connected with a rope, cord, or chain, g. By this means a single rope or chain may be used to lift and lower the tightening-pulley. These devices are so connected that when the belt-shifting arms are in their collapsed or closed position, as shown in Fig. 6, the tightening-pulley is in engagement with the driving -belt; but when the lev r brings the beltshifting arms in engagement with the belt to hold it away from the driving-pulley the tightening-puL ley is lowered or permitted to fall by its own weight and allow the belt to assume the position shown in Fig. 2.

It will also be noted that the positively-actuated arms E are next each other, and that the loose arms E are also next each other, although interposed between the positively-actuated ones, and that both sets move in opposite directions to each other, both in shipping and unshipping the belt-that is to say, one loose and one positively-actuated set of arms move in an opposite direction from the corresponding set on the other side of the shaft.

Having thus fully described the construction, organization, and operation of my improved belt-shifter, what I claim therein as new and as of my invention, and desire to secure by Letter Patent, is-

1. The combination, substantially as hereinbefore set forth, of a shaft, a pulley thereon, a belt encircling the pulley, positivelyactuated shifting-arms movable independently in opposite directions to opposite sides of the pulley, and lifting-bars carried by the shifting-arm s, interposed between the belt and pulley.

2. The combination, substantially as hereinbefore set forth, of a shaft, a pulley thereon, separate sets of radial shifting arms, each set independently pivoted on the shaft and each set separable from each other set, lifting-bars carried by the arms, and devices which positively and simultaneously traverse the lifting-bars over the surface of the pulley and spread them apart.

3. The combination, substantially as hereinbefore set forth, of a shaft, a pulley thereon, separate sets of radial shifting-arms independently pivot-ed on the shaft, lifting-bars carried by the arms, devicescausing at least two sets of arms positively and sim ultaneously to traverse the surface of the pulley in opposite directions, and corresponding sets of separate independently-pivoted shifting-arms interposed between and moved by the corresponding positively-actuated'ones and in the same direction. e

4:. The combination, substantially as hereinbefore set forth, of a shaft, a pulley thereon, separate radial shifting-arms independently pivoted on the shaft on opposite sides of the pulley, a lifting-bar connecting each pair of arms close to and substantially parallel with the face of the pulley, an actuating-lever, and interposed pivoted links respectively connecting the actu ating-lever and corresponding arms on opposite sides of the shaft, to cause the lifting-bars to be moved positively and simultaneously in opposite directions around the driving-pulley.

5. The combination, substantially as hereinbefore set forth, of a shaft, a pulley thereon, separate radial shifting-arms independently pivoted on the shaft on opposite sides of the pulley, a lifting-bar connecting each pair of arms substantially parallel with the face of the pulley, an actuating-lever interposed, pivoted links respectively connecting the actuating-lever, and corresponding arms on opposite sides of the shaft, and interposed arms carrying additional lifting bars or rollers crossing the face of the pulley and movable loosely around the driving-pulley.

6. The combination, substantially as hereinbefore set forth, of a driving-shaft, a driving-pulley thereon, a driven pulley and its shaft, a belt traversing the pulleys, separate sets of radial shifting-arms independently pivoted on the driving-shaft and carrying lifting-bars simultaneously and independently traversing the driving-pulley in opposite directions to lift the belt therefrom.

7. The combination, substantially as hereinbefore set forth, of a driving-pulley, a driven pulley, a belt traversing them, lifting-bars simultaneously traversing the face of the driving-pulley in opposite directions to lift the belt therefrom, and a tightening-pulley mounted in radial arms on the driving-shaft.

8. The belt-shifting apparatus hereinbefore described, consisting of the combination of a driving-sh aft, a driving-pulley, a driven pulley, a belt traversing the pulley, separate radial shifting-arms independently pivoted upon the driving-shaft on opposite sides of the driving-pulley, lifting-bars crossing the face of the driving-pulley and connecting said arms in pairs, actuating-links respectively pivoted to their corresponding arms on opposite sides of the driving-shaft to traverse them simultaneously and positively in opposite directions, interposed lifting-bars carried by concentrically-pivoted arms interposed between the pivotally-actuated ones, and a tighteningpulley movable concentrically with the lifting-bars.

9, The combination, substantially as hereinbefore set forth, of the driving-shaft, the pulley thereon, the belt-shifting arms, their enlarged bearing-surfaces split or opened, as described, at their inner ends, and the sleeve on which the arms are mounted inclosing the shaft.

10. The combination, substantially as hereinb'efore set forth, of the shaft, the pulley, the sectional sleeve thereon, the sectional collars secured to the driving-shaft on each side of the sleeve, and the belt-shifting arms mounted on the sleeve between the collars.

11. The combination, substantially as hereinbefore set forth, of the belt-shifting arms E having lugs or nibs 6 the belt-shifting arms E, with which the lugs or nibs e engage, the driving-shaft, the driving-pulley, the operating-lever', and connections between the operating-lever and the arms E In testimony whereof I have hereunto subscribed my name.

- PHILIP MEDART.

Vitnesses:

LLOYD B. WIGHT, N. H. SMITH, JOHN W. SIMs. 

